From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 86652E9A04C for ; Thu, 19 Feb 2026 08:05:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=EHudbKayVTVVqxJhNX2Ll3zwl/zmMNita3jIyjimtoQ=; b=hTbBFpQe8eIspz a2syZAi3E2uN5Uev77J203zREJDcACVDi3+ViDMFGxoTlvQWOWucxcsFpynPSlPNwOfizaRT6FUFx OhGKFx8NQ0P/ajg8Z136/04dZmnq4G/9OEWfAnHrEe27bgWjz4onq1hVMYGJ1Clr886a6urkRbDaM LTM/3y80RCB69/sgc+4wvNN0rYK1oWKBb6eizpVAceMJTx33YIJgsipa5ufX98wLXI5Ly2RSRE7aQ E6XOI7UYqUU8Wgfk823hn4NW/NcRtGbkKN9Oy4bPBJfsr90UF+fJDBQ4XYfMfV9i4aMS34tlKDOt5 y+4Ql73xyhxwAYN6vDgQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vsz24-0000000B5ei-3gZO; Thu, 19 Feb 2026 08:05:08 +0000 Received: from sender4-op-o15.zoho.com ([136.143.188.15]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vsz22-0000000B5eO-0w0k for linux-riscv@lists.infradead.org; Thu, 19 Feb 2026 08:05:07 +0000 ARC-Seal: i=1; a=rsa-sha256; t=1771488293; cv=none; d=zohomail.com; s=zohoarc; b=ikjtOb3oX1EgHtdw2QAxqKYlVneQSwVpL0ucVwHo2BOn3HB/94myWhKMGQINXwdpOZK3npc4LWXT0YMSrQirMOoIz+sEXFjEdql88wfXp64KGkhIeNFuy7DLDj9rvmm2PWm5g2SNYv/JXH3pBME1YFe7gkhQJ6g4f2N7Z6ohgeM= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1771488293; h=Content-Type:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=kYQ5NkddKGLVG7KXnc5tVWiA8oqeInGD+WTRnEtYdQ0=; b=ca1PRjshbgl0kblWXlxZYjxLz4+EjGHd7r3vw5HoWB6wxiDrLsM3QC5vaKvKz7Clyg5R1kKeapY94Kb4FWBEyZbGPhhgYGjlOgmQXF9gU2aPZ0B26sB778xsKw693Dk8mkTwyV8ivBeFNMZc7EYzJJ10UxCBdOWLTdQ+Sh0piFk= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=ziyao.cc; spf=pass smtp.mailfrom=me@ziyao.cc; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1771488293; s=zmail; d=ziyao.cc; i=me@ziyao.cc; h=Date:Date:From:From:To:To:Cc:Cc:Subject:Subject:Message-ID:References:MIME-Version:Content-Type:In-Reply-To:Message-Id:Reply-To; bh=kYQ5NkddKGLVG7KXnc5tVWiA8oqeInGD+WTRnEtYdQ0=; b=QevocWd9wnFpbz6v8KCBM++Ys6nV8e156lzrioDP5AuZwNKDcNaawITAAg98QsGk Kb2uKNno6Tg11FVRfVCyTILiEQN1MdAM79iW7HpvdQ+22Qf+5kenHshvDOppuegxWjr 7d1YgfTJOZuj6xEGdtMUB56dClW92AivaTYOIfLU= Received: by mx.zohomail.com with SMTPS id 1771488291848192.88439580319414; Thu, 19 Feb 2026 00:04:51 -0800 (PST) Date: Thu, 19 Feb 2026 08:04:42 +0000 From: Yao Zi To: guoren@kernel.org, paul.walmsley@sifive.com, palmer@dabbelt.com, alex@ghiti.fr, leobras@redhat.com, djordje.todorovic@htecgroup.com, aleksa.paunovic@htecgroup.com, arnd@arndb.de, rabenda.cn@gmail.com Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, Han Gao , Alexandre Ghiti , Paul Walmsley Subject: Re: [PATCH V3] riscv: errata: Add ERRATA_THEAD_WRITE_ONCE fixup Message-ID: References: <20260125063941.443777-1-guoren@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20260125063941.443777-1-guoren@kernel.org> X-ZohoMailClient: External X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260219_000506_338073_85EE5BD0 X-CRM114-Status: GOOD ( 14.57 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Sun, Jan 25, 2026 at 01:39:41AM -0500, guoren@kernel.org wrote: > From: "Guo Ren (Alibaba DAMO Academy)" > > The early version of XuanTie C910 core has a store merge buffer > delay problem. The store merge buffer could improve the store queue > performance by merging multi-store requests, but when there are not > continued store requests, the prior single store request would be > waiting in the store queue for a long time. That would cause > significant problems for communication between multi-cores. This > problem was found on sg2042 & th1520 platforms with the qspinlock > lock torture test. > > So appending a fence w.o could immediately flush the store merge > buffer and let other cores see the write result. > > This will apply the WRITE_ONCE errata to handle the non-standard > behavior via appending a fence w.o instruction for WRITE_ONCE(). > > This problem is only observed on the sg2042 hardware platform by > running the lock_torture test program for half an hour. The problem > was not found in the user space application, because interrupt can > break the livelock. > > Reviewed-by: Leonardo Bras > Tested-by: Han Gao > Cc: Yao Zi > Cc: Alexandre Ghiti > Cc: Paul Walmsley > Signed-off-by: Guo Ren (Alibaba DAMO Academy) With the patch, I've run heavy multi-core compilation load on SG2042 for more than 12 hours, and observed no stability issues. Tested-by: Yao Zi Thanks, Yao Zi _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv